Multiple modes are available for completing the last one kilometer broadband data access in a communication system, and the relatively common access mode is implemented through a digital subscriber line (xDSL).
FIG. 1 is a connection schematic diagram of an existing home network accessed through the xDSL. The relatively common broadband communication equipment at a subscriber's side is referred to as customer premises equipment (CPE) or home gateway (HGW) marked with HGW in the figure. A digital subscriber line access multiplexer (DSLAM) and an exchange in a telecommunication central office (CO) of an operator are connected with the HGW and other equipment in the home network through an xDSL twisted pair.
The xDSL twisted pair is employed to transmit data, and may share a line with a public switched telephone network (PSTN) without rewiring. Service treatment is sorted according to different signal frequency bands: analog signal frequency bands of PSTN services are generally smaller than 4 kHz, but data service signals are located in frequency bands larger than 4 kHz. And non-interference may be ensured by proper filtering. That is, the twisted pair in FIG. 1 may bear DSL broadband data and may also bear PSTN telephone services, and the DSL broadband data include asymmetric digital subscriber line (ADSL) broadband data.
A home telephone service system is likely to wire in a subscriber's walls, then interfaces (marked as A/B/C in the figure) are set in different rooms, signals transmitted through the xDSL twisted pair are low-pass filtered in a downlink direction by a filter 2 and a filter 3, and telephone set 2 and telephone set 3 may make a PSTN phone call.
The HGW receives and transmits the DSL broadband data through a twisted pair system; and an HGW may accomplish data interaction by interfacing a DSL interface and the twisted pair system in an uplink direction. The HGW may interface with equipment such as a computer, a set top box, etc. through a fast Ethernet interface (FE) in a downlink direction to realize the function of surfing on the Internet; in a downlink direction, a universal serial bus (USB) interface may link to a printer or a USB storage device to complete corresponding functions; in the downlink direction, a Plain Old Telephone Service (POTS) interface may link to a common telephone set or facsimile apparatus to complete Internet-based voice over IP (VoIP) functions, for example, a telephone set is linked to the POTS interface in the downlink direction. And in the HGW, an analog signal is sampled, compressed, packaged and transformed into data signals which may be accepted by an xDSL protocol to complete data interaction with a DSLAM at the CO. In the process, the conventional analog telephone sets may dial a VoIP telephone.
However, the applicant finds that telephone sets (the telephone set 2 and the telephone set 3) in other rooms can only use PSTN telephone services not VoIP telephone services in the above technical conditions, and this limits available services of the telephones in other rooms.